The United Progressive Party (UPP) leader and labour activist, Baldwin Spencer is being sworn in as prime minister following his party’s victory in Antigua and Barbuda’s general election.

Preliminary results showed the UPP scoring a landslide victory and claiming a 12-4 majority over outgoing prime minister Lester Bird's Antigua Labour Party (ALP).

Mr Bird conceded defeat early on Wednesday - the ALP’s first defeat in 28 years - and a personal blow for the outgoing prime minister who also lost his own seat.

"The people decided it was time for a change. After six consecutive elections the law of averages would say in any event perhaps it would have been very difficult for us to have won a seventh," Mr Bird said.

"There can be no doubt that the Labour Party performed and this election was not contested on the basis of issues, but it was contested on the basis that it was time to give someone else a chance. And obviously the people have spoken," the outgoing prime minister added.

Meanwhile, a victorious Mr Spencer called on his supporters not to denigrate the ALP.

"Vanquished political leaders ought not to be disgraced. The good deeds of vanquished political leaders should be acknowledged," Mr Spencer said.

But Mr Spencer, gave a clear indication that an investigation into the Bird administration would be conducted.

"Crimes against the people should be punished. That is the business of our law enforcement agencies and the judiciary. We will let those chips fall where they may," Mr Spencer said.

The election was marked by corruption charges against Mr Bird’s family dynasty that has dominated Antigua and Barbuda for more than half a century.

Scandals in recent years have centred on allegations of bribery, misuse of and missing funds in the national health insurance plan, and a 13-year-old girl's charges that Mr Bird and his brother used her for sex and to procure cocaine.

Mr Bird denied the last charges. An inquiry into the charges found there was no evidence.

While 16 of the 17 constituencies have been declared there will be fresh elections for the other seat on Barbuda where the UPP and ALP candidates both received 400 votes.

The candidates opted for a fresh poll in Barbuda after they decided against a recount of the ballots.

The Electoral Commission reported a turnout of 75-80 per cent, compared to about 60 percent in 1999.

The ALP had held nine of 17 Parliament seats, to the UPP’s four.

Mr Bird's party had campaigned on a record of 4 per cent economic growth and 10 per cent unemployment in an economy based on sagging tourism and an offshore banking industry critics say is corrupt and pays bribes to government officials.

The UPP campaigned on pledges of greater unemployment benefits and support for school uniforms and lunches.

The Bird family has dominated Antiguan politics since the 1950s, when Vere Bird Sr. was a revolutionary labour leader defying British colonisers to demand higher wages for cane cutters. Mr Bird Snr. led his country to independence in 1981.

Outgoing prime minister, Lester Bird won 1994 elections after his father retired.